Harvard Forest, Harvard University, Petersham, Massachusetts, United States of America.
Department of Biological Sciences, Bowling Green State University, Bowling Green, Ohio, United States of America.
PLoS One. 2021 Nov 10;16(11):e0259045. doi: 10.1371/journal.pone.0259045. eCollection 2021.
Decomposition is an essential ecosystem service driven by interacting biotic and abiotic factors. Increasing temperatures due to climate change can affect soil moisture, soil fauna, and subsequently, decomposition. Understanding how projected climate change scenarios will affect decomposition is of vital importance for predicting nutrient cycling and ecosystem health. In this study, we experimentally addressed the question of how the early stages of decomposition would vary along a gradient of projected climate change scenarios. Given the importance of biodiversity for ecosystem service provisioning, we measured the effect of invertebrate exclusion on red maple (Acer rubrum) leaf litter breakdown along a temperature gradient using litterbags in warming chambers over a period of five weeks. Leaf litter decomposed more slowly in the warmer chambers and in the litterbag treatment that minimized invertebrate access. Moreover, increasing air temperature reduced invertebrate abundance and richness, and altered the community composition, independent of exclusion treatment. Using structural equation models, we were able to disentangle the effects of average air temperature on leaf litter loss, finding a direct negative effect of warming on the early stages of decomposition, independent of invertebrate abundance. This result indicates that not only can climate change affect the invertebrate community, but may also directly influence how the remaining organisms interact with their environment and their effectiveness at provisioning ecosystem services. Overall, our study highlights the role of biodiversity in maintaining ecosystem services and contributes to our understanding of how climate change could disrupt nutrient cycling.
分解是由生物和非生物因素相互作用驱动的一项重要生态系统服务。气候变化导致的温度升高会影响土壤湿度、土壤动物区系，并随后影响分解。了解预测的气候变化情景将如何影响分解对于预测养分循环和生态系统健康至关重要。在这项研究中，我们通过在升温室中使用垃圾袋进行实验，沿着预测的气候变化情景梯度，从实验上探讨了分解的早期阶段将如何变化的问题。鉴于生物多样性对生态系统服务提供的重要性，我们在五周的时间内，在温度梯度下，测量了无脊椎动物排除对红枫（Acer rubrum）叶凋落物分解的影响。在较温暖的温室中和在最大限度减少无脊椎动物进入的垃圾袋处理中，叶凋落物分解得更慢。此外，空气温度的升高降低了无脊椎动物的丰度和丰富度，并改变了群落组成，而与排除处理无关。通过结构方程模型，我们能够区分平均空气温度对叶凋落物损失的影响，发现变暖对分解的早期阶段有直接的负面影响，与无脊椎动物的丰度无关。这一结果表明，气候变化不仅会影响无脊椎动物群落，还可能直接影响剩余生物与其环境的相互作用及其在提供生态系统服务方面的有效性。总的来说，我们的研究强调了生物多样性在维持生态系统服务中的作用，并有助于我们了解气候变化如何可能破坏养分循环。
